Chronic sinusitis (CRS) is a long-standing mucosal inflammatory disease of the sinonasal tract that results in significant impairment in patient quality of life. The pathogenic determinants of disease include chronic mucosal inflammation, local microbial colonization, and mucociliary dysfunction. A thorough understanding of this tripartite model allows for endotyping and tailored therapy. Medical therapy in the form of oral and/or topical therapy is imperative to reduce mucosal inflammation, treat microbial infection, and enhance mucociliary function. Functional endoscopic sinus surgery (FESS) serves to surgically reduce inflammatory load, ventilate the sinuses, augment installation of topical therapy, and provide tissue for endotyping. The end result of well-performed surgery is a unified sinus cavity augmented for improved medical therapy. Newer therapeutics, such as biologic therapies, target TH-2 driven mucosal inflammation and are gaining an emerging role in the management of CRS; however, the role of these therapies is not well defined in the current treatment paradigm. This review contains figures, tables and references Key words: chronic sinusitis, chronic rhinosinusitis, functional endoscopic sinus surgery, topical steroid therapy, endotype, structured histopathology, nasal polyps, biologic therapy, mucociliary dysfunction, biofilms